From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7495FC4345F for ; Fri, 3 May 2024 17:10:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=UYUCpq6mV88oSUxwZxdjYhSuoy/0qamrxpy6gRlFzcM=; b=gRCxfEmnbeTmH1 SJN2El8iKKU9kORBglaPZMhp8ED0C+joJtwlIwkAQN2vT4/btjUkjz2BRV1in91SkDpmD8aq5csLQ RVByQIi4aX7MfQIeD4ObJtrtkIA+QGh8emHcq5nvD/0grhNhkpwL7JPD6yZ7bLjt7aoq3903bhDKm EMJ+JVkNfrW1tN8lG8EmsyGWOAkqsh1cycgqnIfRdotWsKKAxa5WgQ5v08ZmJtLdwLajav4SyQ+Ix w8bVt4vzxFjbypeTODkvoOTIY/7ibc3MMaqPoWy/Hszp3XryVb3Uc5DQ8mqDcqw1ZmxR7JWRSXy6K fKoeQ+NLQyymyJaziKgg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1s2wQZ-0000000HKzU-3MeI; Fri, 03 May 2024 17:10:31 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1s2wQW-0000000HKxt-1mot for linux-arm-kernel@lists.infradead.org; Fri, 03 May 2024 17:10:30 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9BCD713D5; Fri, 3 May 2024 10:10:49 -0700 (PDT) Received: from FVFF77S0Q05N (unknown [10.57.34.156]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3ED0E3F793; Fri, 3 May 2024 10:10:18 -0700 (PDT) Date: Fri, 3 May 2024 18:10:14 +0100 From: Mark Rutland To: Liao Chang Cc: catalin.marinas@arm.com, will@kernel.org, maz@kernel.org, oliver.upton@linux.dev, james.morse@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, tglx@linutronix.de, ardb@kernel.org, broonie@kernel.org, anshuman.khandual@arm.com, miguel.luis@oracle.com, joey.gouly@arm.com, ryan.roberts@arm.com, jeremy.linton@arm.com, ericchancf@google.com, kristina.martsenko@arm.com, robh@kernel.org, scott@os.amperecomputing.com, songshuaishuai@tinylab.org, shijie@os.amperecomputing.com, akpm@linux-foundation.org, bhe@redhat.com, horms@kernel.org, mhiramat@kernel.org, rmk+kernel@armlinux.org.uk, shahuang@redhat.com, takakura@valinux.co.jp, dianders@chromium.org, swboyd@chromium.org, sumit.garg@linaro.org, frederic@kernel.org, reijiw@google.com, akihiko.odaki@daynix.com, ruanjinjie@huawei.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev Subject: Re: [PATCH v3 0/8] Rework the DAIF mask, unmask and track API Message-ID: References: <20240415064758.3250209-1-liaochang1@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20240415064758.3250209-1-liaochang1@huawei.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240503_101028_743669_A92C1C21 X-CRM114-Status: GOOD ( 24.09 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On Mon, Apr 15, 2024 at 06:47:50AM +0000, Liao Chang wrote: > This patch series reworks the DAIF mask, unmask, and track API for the > upcoming FEAT_NMI extension added in Armv8.8. > > As platform and virtualization[1] supports for FEAT_NMI is emerging, and > Mark Brown's FEAT_NMI patch series[2] highlighted the need for clean up > the existing hacking style approach about DAIF management code before > adding NMI functionality, furthermore, we discover some subtle bugs > during 'perf' and 'ipi_backtrace' transition from PSEUDO_NMI to > FEAT_NMI, in summary, all of these emphasize the importance of rework. > > This series of reworking patches follows the suggestion from Mark > Rutland mentioned in Mark Brown's patchset. In summary, he think the > better way for DAIF manangement look likes as following: > > (a) Adding entry-specific helpers to manipulate abstract exception masks > covering DAIF + PMR + ALLINT. Those need unmask-at-entry and > mask-at-exit behaviour, and today only need to manage DAIF + PMR. > > It should be possible to do this ahead of ALLINT / NMI support. > > (b) Adding new "logical exception mask" helpers that treat DAIF + PMR + > ALLINT as separate elements. I've started looking at this in the series. There are some subtleties here, and I don't think the helpers in this series are quite right as-is. I will try to get back to you next week with a description of those; it'll take a short while to write that up correctly and clearly and I don't trust myself to rush that last thing on a Friday. Thanks, Mark. > > This patches cherry-pick a part of Mark Brown' FEAT_NMI series, in order > to pass compilation and basic testing, includes perf and ipi_backtrace. > > [1] https://lore.kernel.org/all/20240407081733.3231820-1-ruanjinjie@huawei.com/ > [2] https://lore.kernel.org/linux-arm-kernel/Y4sH5qX5bK9xfEBp@lpieralisi/ > > v3->v2: > 1. Squash two commits that address two minor issues into Mark Brown's > origin patch for detecting FEAT_NMI. > 2. Add one patch resolves the kprobe reenter panic while testing > FEAT_NMI on QEMU. > > v2->v1: > Add SoB tags following the origin author's SoBs. > > Liao Chang (5): > arm64: daifflags: Add logical exception masks covering DAIF + PMR + > ALLINT > arm64: Unify exception masking at entry and exit of exception > arm64: Deprecate old local_daif_{mask,save,restore} > irqchip/gic-v3: Improve the maintainability of NMI masking in GIC > driver > arm64: kprobe: Keep NMI maskabled while kprobe is stepping xol > > Mark Brown (3): > arm64/sysreg: Add definitions for immediate versions of MSR ALLINT > arm64/cpufeature: Detect PE support for FEAT_NMI > arm64/nmi: Add Kconfig for NMI > > arch/arm64/Kconfig | 17 ++ > arch/arm64/include/asm/cpufeature.h | 6 + > arch/arm64/include/asm/daifflags.h | 298 ++++++++++++++++++++++----- > arch/arm64/include/asm/nmi.h | 27 +++ > arch/arm64/include/asm/sysreg.h | 2 + > arch/arm64/include/uapi/asm/ptrace.h | 1 + > arch/arm64/kernel/acpi.c | 10 +- > arch/arm64/kernel/cpufeature.c | 58 +++++- > arch/arm64/kernel/debug-monitors.c | 7 +- > arch/arm64/kernel/entry-common.c | 96 +++++---- > arch/arm64/kernel/entry.S | 2 - > arch/arm64/kernel/hibernate.c | 6 +- > arch/arm64/kernel/irq.c | 2 +- > arch/arm64/kernel/machine_kexec.c | 2 +- > arch/arm64/kernel/probes/kprobes.c | 4 +- > arch/arm64/kernel/setup.c | 2 +- > arch/arm64/kernel/smp.c | 6 +- > arch/arm64/kernel/suspend.c | 6 +- > arch/arm64/kvm/hyp/vgic-v3-sr.c | 6 +- > arch/arm64/kvm/hyp/vhe/switch.c | 4 +- > arch/arm64/mm/mmu.c | 6 +- > arch/arm64/tools/cpucaps | 2 + > drivers/irqchip/irq-gic-v3.c | 6 +- > 23 files changed, 442 insertions(+), 134 deletions(-) > create mode 100644 arch/arm64/include/asm/nmi.h > > -- > 2.34.1 > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel